摘要：绝大多数的特种可裂变材料钚均存在于商用乏燃料组件中,在核保障领域,对于乏燃料组件中钚含量的核实显得尤为重要。为分析计算乏燃料组件中易裂变核素钚的含量,以31组AFA-2G典型压水堆乏燃料组件为研究对象,通过分析核燃料在反应堆运行过程中的U-Pu循环燃耗链的特点,分析计算了乏燃料组件中主要同位素的含量和固有中子本底,同时利用蒙特卡罗模拟方法计算了239Pu等效质量的等效系数。本文工作为中子质询乏燃料组件易裂变核素含量非破坏性测量的方法研究及测量装置的设计打下了基础。

摘要：The design of a lead slowing down spectrometer is being developed at KAERI (Korea Atomic Energy Research Institute) for an analysis of isotopic fissile content in spent and recycled fuel. The lead spectrometer has an advantage to assay fissile content directly from spent fuel. Accurate fissile material data must be fed back to the spent fuel design and management. For reutilization of PWR spent fuel, an isotopic fissile content analysis is required to obtain safety and economics in the fuel cycle. The LSDS (lead slowing down spectrometer) uses the different fission signatures of each fissile with respect to the interrogation neutron energy. Several simulations were done and parameter was obtained for the system working. Energy between 1 keV to 0.1 eV is very sensitive to isotopic fissile material fission with good energy resolution. An external source neutron is necessary to induce enough fissile fission. A neutron production methodology is being developed for cost effectiveness, easy maintenance and high neutron yield rate. The threshold fission detector screens the prompt fast fission neutrons from an intense radiation background. The detection of a fission signature has a direct relationship with the isotopic fissile content.